A variety of orally activated valves have been developed for hydration systems and for containers. Closures for these types of applications typically incorporate a flexible, self-sealing, slit-type dispensing diaphragm valve mounted on a delivery tube or at a container outlet.
Typically, closures of this type employed on containers utilize multiple piece housings or bodies in which the valve is mounted. While closures used for such applications may function generally satisfactorily, in some applications it is desirable not to employ multiple piece constructions. Further, there is a need for an improved closure which can be more easily manufactured and assembled with reduced manufacturing costs.
In the field of hydration systems or systems for delivering liquid to the mouth of the user wherein valves are attached to delivery tubes, it would be advantageous to employ a valve that has a high flow rate but utilizes a small diameter housing that the user holds in his or her mouth. It would also be advantageous for the valve to open by the same action the user would use to drink; that is, the suction action that naturally occurs while drinking should open the valve. Then, when the user stops drinking, the valve should close. In addition, when the valve is released from the user's mouth the valve should remain closed and be in a leak tight condition; the pressure exerted by the fluid remaining in the tube should not force the valve open. The valve assembly should also prevent back flow of fluid from the valve back into the container.
As will be seen below, the apparatus disclosed and claimed herein meets these objectives. This is accomplished by employing a combination of structural elements which cooperate in a unique manner as compared to prior art approaches. These structural elements include a gravity sensitive valve in operative association with a pressure activated valve spaced a predetermined distance from the gravity sensitive valve in a fluid flow passageway.
U.S. Pat. No. 5,730,336, issued Mar. 24, 1998, discloses a bite valve with a uniform lip extending from the outlet end of the valve. The valve has a concave diaphragm facing the outlet. The diaphragm can have parallel or intersecting slits cut in it. Intersecting slits can be radially symmetrically disposed about the cylindrical axis of the valve.
U.S. Design Patent No. Des.350,672, issued Sep. 20, 1994 illustrates a valve on a container that incorporates many features disclosed in U.S. Pat. No. 5,730,336. The exit valve is formed of a cylindrical body having a uniform lip that extends from the outlet end of the valve. A curved diaphragm employed on the container or bottle is concave in the direction of the outlet and the diaphragm has two slits that intersect at the cylindrical axis of the valve.
U.S. Pat. No. 5,743,443, issued Apr. 28, 1998, discloses a valve on a container incorporating features similar to those illustrated in Des.350,672.
U.S. Pat. No. 3,822,720, issued Jul. 9, 1974, discloses a duck-bill type check valve with a single slit made of resilient material.
U.S. Pat. No. 2,219,604, issued Oct. 29, 1940, teaches a resilient valve with a single slit cut in the tip of the exit end of the valve. The area where the slit it made is at the tip of a domed or convex structure oriented toward the outlet side of the valve.
U.S. Pat. No. 5,060,833, issued Oct. 29, 1991, shows a bite valve for a hydration system employing a ball and spring arrangement with a sealing seat. The sealing seat can be on the upstream or the downstream side of the valve, but not both. The ball of the valve is disengaged from the surface of the sealing seat by deforming the body of the valve. This allows the fluid to around the ball and exit the delivery tube. This results in a relatively low fluid flow rate and requires the user to deform the external walls of the valve to cause fluid flow.
U.S. Pat. No. 5,085,349, issued Feb. 4, 1992, discloses a bite valve for a hydration system wherein the user must deform the external walls of the valve to allow fluid flow. There is the potential for the valve to leak if the sealing surfaces of the slit degrade or if the slit tears past the original cut. Also, if the user bites the valve with only his or her teeth and the user's mouth is not wrapped around the valve, fluid inside the tube can flow back into the hydration system reservoir.
My U.S. Pat. No. 5,601,207, issued Feb. 11, 1997, and U.S. Pat. No. 5,791,510, issued Aug. 11, 1998, disclose systems employing a bite valve for a hydration system where the user must deform the external walls of the valve to make fluid flow. There is the potential for the valve to leak if the sealing surfaces of the slits degrade or if the slits tear past the original cut. Also, if the user bites the valve with only his or her teeth and the user's mouth is not wrapped around the valve, fluid inside the tube can flow back into the hydration system reservoir.
U.S. Pat. No. 5,553,726, issued Sep. 10, 1996, illustrates and describes a pressure activated valve with a cross slitted flat diaphragm. The diaphragm does not open widely when suction is applied to the outlet opening and flow is restricted.
U.S. Pat. No. 3,424,157, issued Jan. 28, 1969, and U.S. Pat. No. 4,993,568 show baby bottle nipples with a slitted tip and a slitted intermediate flat diaphragm that is downstream from the exit opening. These structures have a limited flow rate and no means to prevent back flow.
U.S. Pat. No. 5,301,858, issued Apr. 12, 1994, discloses a hydration system with a mouth piece that has a one-way valve that allows fluid to flow up to the user. The valve must be deformed to allow fluid flow. The arrangement inherently has a low flow rate.
U.S. Pat. No. 4,987,740 shows a diaphragm for venting master cylinders. The valve has a diaphragm with a bellows arrangement for flexing the diaphragm. The diaphragm has a single slit in the center. The bellows and diaphragm configuration is molded of a single piece of resilient material and must be attached to the housing of the master cylinder.
Also known are prior art arrangements wherein a resilient diaphragm structure similar to that disclosed herein; however, the diaphragm is molded separately from the valve housing and considerable handling and manufacturing expenses are involved. One such arrangement is shown in U.S. Pat. No. 5,307,955, issued May 3, 1994, wherein the hinged invertible diaphragm must be molded separately from the container or the closure. The diaphragm is held in the outlet opening by press fitted hard fixtures.
Other features, advantages, and objects of the present invention will become apparent with reference to the following description and accompanying drawings.